Fixing "Fore" -> "For" typo in README docs. (#4317)
Fixing "Fore" -> "For" typo in README docs. (#4317)

Also obeying an 80-column limit for the content and
adding a missing "``virtualenv``" in the phrase
"``pip`` and ``virtualenv``" in some of the docs.
googleapis/python-runtimeconfig,googleapis/python-runtimeconfig